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E4OD tugger kit pump mods


Red Skull Member
May 20, 2020
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Central Iowa
Has anyone done this?

I am wondering what drill bit sizes people have used, mostly on the pump to control tc lockup.
I think the original hole is around .063
The kit calls .073 normal
.083 firm
And .093 firmest.

I want a quick firm lockup but don't want to overdue it. Changing this size again means dropping the trans.

From what I have read online I find use the .093 to omg don't go that big.

This is on a 95 f350 diesel 4x4 that will do some towing.

Going with a new triple disc converter will change lockup by itself but converter manufacturer says their lockup is still gentle.

Opinions? Experience?
I didnt do Tugger's kit, i did Superior's Pump Correction Package, to an E4OD that originally came behind a 302 (now behind a 351). No mods to the plate, only the pump. Amongst other things, they have you drill that orifice out to .093.

So i did mine, along with a Punisher valve body, to an otherwise stock E4OD. I think the lockup is pretty nice. Nice & firm but not harsh. The 1-2 shift is pretty tight, but thats more a function of the valve body id assume.

I do have a fully built E4OD behind my 7.3 but i didnt build it myself so i cant say for sure what all they did.
I ended up drilling it to .085.

Kind of in between. I chickened out going all the way. I want it to feel like another gear but I probably already went too far.

I will add that the drill bits they send and even many small bits you buy are not the size they claim to be.

I used a micrometer and found most drill bits to be .001-.002 under there claimed size.
Often a the hole may end up at the rated size but just a heads up if you are a perfectionist.

I have done this kit behind a 302 and cannot at all remember what sizes I used.
But then the dynamics of the diesel are different anyway.

Still have to drill the plate for the other shifts, 2-3-4
Seems from reading most guys that chose the smaller sizes thought 1-2 was great but 2-3 and 3-4 were soft so I will probably increase those some over the smallest safe sizes.
at least these can be changed by dropping the pan only

Another note, seems like the idi diesel guys drill them all out to the max or even more and like it that way but I believe the idi does not change line pressure based on throttle position like the power strokes and never diesels.

Ultimately I think my quest it to have a trans that shifts more like 5r110 or newer diesel models.

I am even willing to do a stand alone computer but maybe it just isn't possible. Maybe it will always be clumsy.

Trans parts are still trickling in. Hope to start reassembly soon
I used a micrometer and found most drill bits to be .001-.002 under there claimed size.
Often a the hole may end up at the rated size but just a heads up if you are a perfectionist.

drill bits are not reamers
if they were on size they'd make oversize holes
[486 said:

drill bits are not reamers
if they were on size they'd make oversize holes

You are exactly right.
i should have explained better.

Going through all my bits, plus the ones in the kit and onesI bought there was .001-.002 between bits based on brand and design.

In the end the hole may end up the proper size but trying to find the correct bit can drive you nuts.
I wonder if that is why so many people just use a 3/32 bit and call it a day.
Are you rebuilding your E4OD yourself?

Post up pics documenting it. Link it. I'm interested, if it's not horrible. I want the same thing, nice firm shifts that don't break my teeth behind a PowerStroke.
I wonder if that is why so many people just use a 3/32 bit and call it a day.

3/32 = .09375. Pretty sure its close enough for what were talking about doing.

Are you rebuilding your E4OD yourself?

Post up pics documenting it. Link it. I'm interested, if it's not horrible. I want the same thing, nice firm shifts that don't break my teeth behind a PowerStroke.

Here's a really good writeup on rebuilding the E4OD:


Of course, Supermotors is down again, so youll have to check it later, to see the pics.

If interested, i took pics of Superior's Pump Correction Package, you can see that here:

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I am intimately familiar with the that thread on FDB.
I have also read through your thread.

There are far better videos and pics than anything I can do, besides I am kind of tired of doing write ups. It's nice just to focus on the work.

Another awesome read is, most of it is pretty accurate. Trackspeeder is pretty smart as he replies in that thread as well, so follow his tips.

Covers all the bulletproof upgrades and you can see the problems a person runs into when trying to do it correctly from your garage and not having all kinds of extra parts laying around.

I am not going to do all the upgrades, I have already invested $2k in parts and don't see the need to spend at least another $800 on billet parts and planetaries when mine appears almost perfect and have already had more abuse than it will ever get again. Plus some of those parts are getting harder to find.
I'll never go over 300 hp or 700 ft/lbs and the stock trans held up to that very well. I am also lucky that mine is a 95 so most of the factory updates are already in it as well as having the good pump.

I would not have done this much but I did finally find some wear on the direct clutch. You could still read the logo on the frictions but some of the lines were worn flat. No telling how long that wear was there.
Bought torque converter and clutch kit from racer x usa, so far not happy with their shipping. Need to call them again. 3 weeks now on the converter and 2 weeks on the overhaul kit and still waiting.

On these drill bit sizes nobody is going to notice a .005 difference. I think very few will notice a .010 difference. For me this is more of a reference and a place to keep track of what I did and where I started. You can always go bigger.

When I did the Sonnax kit years ago, (that kit is springs in valve body only) The truck had very firm shifts and operated perfectly for a few years. When the OEM converter failed in the middle of no where I got whatever I could get at the local tranny shop. I knew driving away things were not right. My crisp firm shifts were gone.
That converter only lasted a couple thousand miles. The next converter improved my shifts but they were still not as good as the OEM converter shifts.

So I am really interested to see what this new converter will be like, they do make a difference in transmission performance. Not just lock up.

I think I have ordered,
New Solenoid pack.
45 element sprag
sonnax pump gears
Sonnax front lube drain back valve
Trans Go 4R100-hd2
Bushing kit
Stage 3 overhaul kit with red eagle frictions and kolene steels. But after the kit arrived I see it has the cheapest crappiest seals. Also I was not able to even get close to any of the clutch pack clearances I wanted to see and I am not modifying old frictions and steels to tighten them up so I ordered another kit. This kit was under $300.
Extra Clutch kit with Red eagle frictions and kolene steels from racer X which includes high temp gasket and seal set.
Snap ring clearance set from Racer X (between this and the two friction kits I should be able to keep every clutch pack .020-.025 That is my intent.
Eagle series billet triple disc converter from racer X. Technically not a low stall, but lower stall than OEM. (My setup will not work well with the low stall)

I drive this thing all over the country. If I was just local you could have done this a lot cheaper. I am also wondering if it would be better to start with a 4R100 and build it as it has better parts in it already.
Sonnax's Spiral snap ring.

Yes, that is a required upgrade. The Tugger kit I bought was for the 4R100 it included a spiral snap ring and coast clutch snap ring.
My OD Snap ring was just laying in the case when I tore the trans down.

I got the pump on today. I have spend more time on this trans than any other in my life. All my clearances are .020-,030 if this trans doesn't shit quick I don't know what will.

It would be helpful to have all the parts and do these start to finish but I still don't have my bonded Band Servo. This pandemic crap has made shipping a pain in the butt. I will probably order another.
I almost missed a snap ring in one pinion set and almost missed a spring in the pump. Too Many distractions.
Ok i wasnt sure if you bought the E4OD or 4R100 kit. I was down to the center support in one of mine, never did a full rebuild. Spread it out over a few days to make sure i didnt make any mistakes. Fairly straightforward to rebuild, but as im sure youre aware, these things need to be assembled perfectly for them to work right, and last.
Another helpful hint I'll give y'all

I originally ordered a generic red eagle/kolene steel kit off the web. It was like $290. Even though it has the good or best frictions and steels the gasket/seal set was the cheap crap.
The front pump seal was gray in color. If you have one of those don't use it. At least on a diesel, it can't handle the heat.
This kit also had new check balls for the valve body, they were green and they felt funny. There also was no sealing rings in the kit, minus the pump, so the intermediate and direct clutches you would have to use your old ones. Then with this kit you would have to modify old frictions and steels, or the pressure plate to get your clearances correct or at least closer.
After trying to use this cheaper kit I was not able to get get the forward clutch pack or reverse clutch pack close at all. That is when I gave up and ordered another complete kit.

I got an extra clutch kit from Racer X usa. It was $550. Then I got the clearance kit that was another $25 I think. Right out of the box, this overhaul kit is far better than the previous kit I bought. All of the sealing rings are there, cast ones too, not teflon. Each clutch pack is labeled as if you couldn't figure it out anyway. The extra clutch kit also has the red eagle/kolene steels. It comes with machined pressure plates so you can add an extra clutch in every forward pack. It had normal check balls in it.
I was assuming the frictions and steels would be a different thickness to make room for the extra clutch but that is not the case. Well except for the overdrive set, it does have thinner frictions.

Not a big fan of thinner pressure plates, but the only one that made me nervous was the overdrive. It seemed tiny.

Even though the frictions and steels were the same out of both kits there are still tolerances. So I pulled all of the reverse steels and frictions from both kits. sat down measured them all, laid them out. Then tried different stacks to get what I want. You can find up to .005 differences between the thickest and thinnest. Without the extra kit I probably would not have gotten the tolerances I wanted.
I would start by trying all the thickest plates. Once I get it together I measure the clearance and see what I need to make up or change. I think one stack I ended up using all the thinnest materials and adding an extra steel. It was that far off.
If this was a gas engine I wouldn't care. Just get it within factory tolerances would have been fine. In that situation the tugger kit would make up for the sloppiness in clearances.

I have most of a complete overhaul kit with red eagle frictions/ kolene steels. So I guess I need to find another project with an E4OD.

My bonded servo piston should be here tomorrow, then I can put the valve body on and maybe install this thing on Wednesday.

I wrote down the sizes I drilled the calibration plate too, I think I did the smallest recommended on 1-2 shift. But went almost to the largest on 2-3 and 3-4.
Okay final hole sizes
1-2 shift .110
2-3 shift .082
3-4 shift .096

Light and medium throttle, stock without chip it is freaking amazing. I love it. Super quick not harsh.
Full throttle, way too harsh.

This is stock computer but I usually have trans stuff omitted from my chip tunes anyway.
I know the ecm on the power stroke in stock form is a learning computer does it also adjust the epc? And shift points?
Like the 5r55e in the explorer with that it is impossible to get a firm shift because the computer controls the epc so it is a soft girly man shift.

Torque converter is ok. Instant and not harsh. I wanted firmer. It also engages early, kind of piles up on 3rd gear.

I'll drive it more but unless it changes with chip I will be putting in a calibration plate with smaller holes.

Right now I am still learning towards a stand alone trans controller.
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